Powder coating composition with brilliant metal effect and coating of powder coating composition

Abstract

The invention discloses a powder coating composition with a brilliant metal effect and a coating thereof, the powder coating composition comprises a powder coating base powder composition and effect pigments, at least one effect pigment is attached to the powder coating base powder composition, and the powder coating base powder composition comprises an organic dye; after the specific powder coating composition is sprayed, heated and cured, the organic dye can be migrated to the surface of the coating due to heating, and especially when the surface is provided with a finishing coating, the organic dye can be migrated to the finishing coating, so that the coating shows a high-brightness metal effect decorative appearance.

Description

Technical Field

[0001] The invention belongs to the field of powder coatings, and in particular relates to a powder coating composition with brilliant metal effect. The invention also relates to a brilliant metal effect coating prepared by using the powder coating composition. Background Art

[0002] Thermosetting powder coatings are widely used to replace paints and water-based paints to achieve protective decoration of products in various fields because of their advantages of being green, low energy consumption, easy to apply, and no (or at least very little) VOC emissions. In order to further facilitate the decorative effect, powder coatings with metallic effects have been widely used in various fields. However, the market still lacks thermosetting powder coating products with both bright color effects and metallic effects.

[0003] Therefore, the applicant hopes to conduct research and development to solve the above technical problems. Summary of the invention

[0004] In view of this, the object of the present invention is to provide a powder coating composition and a coating thereof having a bright metallic effect. After the specific powder coating composition is sprayed and heat-cured, the organic dye will migrate to the surface of the coating due to the heat. In particular, when the surface is provided with a topcoat, the organic dye will (at least to some extent) migrate into the topcoat, so that the coating presents a highly bright metallic effect decorative appearance.

[0005] The technical solution adopted by the present invention is as follows: A powder coating composition with brilliant metallic effect comprises a powder coating base composition and an effect pigment, wherein at least one effect pigment is attached to the powder coating base composition, wherein the powder coating base composition comprises an organic dye.

[0006] Preferably, the organic dye comprises anthraquinone organic dye, and preferably consists of anthraquinone organic dye.

[0007] Preferably, the weight ratio of the organic dye to the powder coating primer composition is 0.1-3 wt %.

[0008] Preferably, the powder coating primer composition is transparent or at least translucent after being cured.

[0009] Preferably, the raw materials of the powder coating base powder composition include polyester resin and a curing agent for curing the polyester resin; the weight ratio of the polyester resin to the powder coating base powder composition is preferably not less than 55wt%, more preferably 65-95wt%, and further more preferably 70-92wt%; the weight ratio of the curing agent to the powder coating base powder composition is preferably not more than 20wt%, more preferably 2-15wt%.

[0010] Preferably, the viscosity of the polyester resin at 200° C. is in the range of 1500-4500 mPa.s, more preferably 2000-4000 mPa.s, and / or the acid value thereof is not higher than 45 mgKOH / g, more preferably 25-40 mgKOH / g.

[0011] Preferably, a brilliant metallic effect coating is obtained by spraying and curing the powder coating composition having brilliant metallic effect as described above on a substrate.

[0012] Preferably, a brilliant metallic effect coating comprises a cured coating and a finishing coating located on the surface of the cured coating, wherein the cured coating is obtained by spraying and curing the powder coating composition having a brilliant metallic effect as described above on a substrate.

[0013] It should be noted that the acid value detection standard involved in this application is based on ISO 3682-1998; the viscosity value detection standard involved is based on ASTM D 4287-1994, and the detection equipment used can be a standard commercial cone and plate viscometer (for example, ICI cone and plate viscometer (CONE & PLATE), brand CAP 2000VISCOMETER from Brookfield).

[0014] The present application proposes a specific powder coating composition formula consisting of a powder coating base composition containing an organic dye and an effect pigment. The applicant was pleasantly surprised to find that after the specific powder coating composition was sprayed and heated and cured, the organic dye would migrate to the coating surface due to the heat (at least to some extent), especially when the surface is provided with a topcoat (i.e., a transparent coating), the organic dye would migrate (at least to some extent) into the topcoat, so that the coating presents a highly vivid metallic effect decorative appearance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a real photo of the bright color metallic effect coating corresponding to Example 1. DETAILED DESCRIPTION

[0016] The embodiment of the present application proposes a powder coating composition with a brilliant metallic effect, comprising a powder coating base composition and an effect pigment, wherein at least one effect pigment is attached to the powder coating base composition, wherein the powder coating base composition comprises an organic dye.

[0017] Preferably, at least 5% of the effect pigments are attached to the powder coating base composition, more preferably at least 10%, even more preferably at least 20%, still more preferably at least 30%, most preferably at least 50% of the effect pigments are attached to the powder coating base composition.

[0018] Preferably, in the present embodiment, the organic dye comprises anthraquinone organic dye, more preferably, in the present embodiment, the organic dye consists of anthraquinone organic dye; preferably, in the present embodiment, the weight ratio of the organic dye to the powder coating base powder composition is 0.1-3wt%, more preferably 0.2-3wt%, and even more preferably 0.5-1.5wt%.

[0019] Preferably, in order to further facilitate obtaining a more excellent brilliant metallic effect, in the present embodiment, the powder coating base powder composition is transparent or at least translucent after curing; it should be noted that the transparency or translucent state involved in the present application means that the coating of the powder coating base powder composition after curing is at least translucent or partially translucent; further preferably, in order to further facilitate the light transmission effect of the coating, in the present embodiment, it is recommended not to add too much pigment / filler to the powder coating composition, wherein the weight proportion of pigment / filler to the powder coating composition is preferably not higher than 15wt%, more preferably not higher than 8wt%, and further preferably not higher than 5wt%.

[0020] Preferably, in the present embodiment, the raw materials of the powder coating primer composition include a polyester resin and a curing agent for curing the polyester resin; preferably, in the present embodiment, the weight proportion of the polyester resin in the powder coating primer composition is not less than 55wt%, more preferably 65-95wt%, and further more preferably 70-92wt%; preferably, in the present embodiment, the viscosity range of the polyester resin at 200°C is 1500-4500mPa.s, more preferably 2000-4000mPa.s; and / or preferably, in the present embodiment, the acid value of the polyester resin is not higher than 45 mgKOH / g, more preferably 25-40 mgKOH / g; specifically preferably, in the present embodiment, the polyester resin is GH-3331 provided by Zhejiang Guanghua, which has a viscosity range of 2500-3500mPa.s at 200°C and an acid value range of 32-37 mgKOH / g.

[0021] Preferably, in this embodiment, the weight ratio of the curing agent to the powder coating base powder composition is not higher than 20wt%, more preferably 2-15wt%; preferably, in this embodiment, the curing agent includes TGIC (triglycidyl isocyanurate) and / or hydroxyalkylamide; further preferably, in this embodiment, the curing agent is TGIC and / or hydroxyalkylamide.

[0022] In the present embodiment, the effect pigment can select a suitable effect pigment according to actual needs, and the present embodiment has no particular limitation on it. Specifically, aluminum powder (including coated aluminum powder) and / or pearlescent pigment (including coated pearlescent pigment) and / or mica (including coated mica) can be selected; preferably, in the present embodiment, in order to further facilitate the brilliant metal effect, in the present embodiment, the effect pigment includes aluminum powder; preferably, in the present embodiment, the weight proportion of the effect pigment to the powder coating primer composition is 0.5-5wt%, more preferably 1-3wt%; preferably, in the present embodiment, the average particle size of the effect pigment is 10-20 microns, and the average particle size is the D50 particle size obtained by particle size distribution test using laser diffraction (for example, using Malvern particle size analyzer 2000), and the test standard is ISO 13320-2009.

[0023] All kinds of raw materials involved in this application can be directly purchased on the market, and the sources of raw materials are easy to obtain.

[0024] In the specific implementation of the present application, known leveling agents, degassing agents, antioxidants, dispersants, fillers, pigments, stabilizers, curing accelerators, functional additives and / or other additives may also be added to the powder coating base powder composition. These are conventional technical choices of those skilled in the art; specifically, fillers and / or pigments may be, for example, carbon black, aluminum hydroxide, barium sulfate, TiO2, etc.

[0025] When preparing the powder coating base powder composition of the present application, any known preparation process can be used for preparation; preferably, in this embodiment, the powder coating base powder composition is obtained by mixing, melt extrusion, and crushing. Of course, other known preparation processes can also be used to obtain the powder coating base powder composition of this embodiment, and the present application has no particular limitation on its preparation process.

[0026] Preferably, in this embodiment, the effect pigment is bonded to the coating base powder composition by a thermal bonding process.

[0027] Preferably, in this embodiment, the thermal bonding process can adopt any known thermal bonding (bonding) process, and this embodiment does not specifically limit it; preferably, in the thermal bonding process, the thermal bonding temperature is recommended to be set at 50-60°C, preferably 50-55°C, and the thermal bonding time is recommended to be selected at 2-5 minutes.

[0028] Preferably, this embodiment provides a brilliant metallic effect coating, which is obtained by spraying and curing the powder coating composition with brilliant metallic effect as described above on a substrate.

[0029] More preferably, the present embodiment proposes a brilliant metallic effect coating, comprising a cured coating and a finishing coating located on the surface of the cured coating, wherein the cured coating is obtained by spraying and curing the powder coating composition having a brilliant metallic effect as described above on a substrate; it should be particularly noted that after the finishing coating is provided, the brilliant metallic effect obtained is significantly better, therefore, the applicant recommends adopting this embodiment (the present invention is not limited to this embodiment).

[0030] In order to verify the technical effect of the present application, the present application specifically conducted the following multiple groups of examples as raw materials for powder coating composition formulations for specific test performance comparison: Example 1: A powder coating composition with a brilliant metallic effect, comprising 98 wt% of a powder coating base composition and 2 wt% of aluminum powder (brand name: POWDAL from SCHLENK) ® 8500 HC); the aluminum powder is compounded with the powder coating primer composition through a thermal bonding process, wherein in the thermal bonding process, the thermal bonding temperature range is 54° C. and the thermal bonding time is 2 minutes; In this embodiment 1, the powder coating primer composition is prepared according to the formula raw materials shown in Table 1 below:

[0031] Example 2: The remaining technical solutions of Example 2 are the same as those of Example 1, except that in Example 2, the polyester resin grade in Example 1 is replaced by CRYLCOAT ® 4642-3 polyester resin, its viscosity at 200°C ranges from 1500-2300 mPa.s, and its acid value ranges from 32-38 mgKOH / g.

[0032] Example 3: The rest of the technical solutions of Example 3 are the same as those of Example 1, except that, in Example 3, the polyester resin brand in Example 1 is replaced by GH-3337 polyester resin provided by Zhejiang Guanghua, which has a viscosity range of 4300-5500 mPa.s at 200°C and an acid value range of 50-56 mg KOH / g.

[0033] Example 4: The rest of the technical solutions of Example 4 are the same as those of Example 1, except that, in Example 4, the polyester resin brand in Example 1 is replaced by Excalibur's SJ3B, which has a viscosity range of 3500-5000 mPa.s at 200°C and an acid value range of 68-75 mgKOH / g.

[0034] Embodiment 5: The remaining technical solutions of Embodiment 5 are the same as those of Embodiment 1, except that, in Embodiment 5, the powder coating primer composition is prepared according to the formula raw materials shown in Table 2 below:

[0035] Embodiment 6: The remaining technical solutions of Embodiment 6 are the same as those of Embodiment 1, except that, in Embodiment 6, the powder coating primer composition is prepared according to the formula raw materials shown in Table 3 below:

[0036] Embodiment 7: The remaining technical solutions of Embodiment 7 are the same as those of Embodiment 1, except that, in Embodiment 7, the powder coating primer composition is prepared according to the formula raw materials shown in Table 4 below:

[0037] Embodiment 8: The remaining technical solutions of Embodiment 8 are the same as those of Embodiment 1, except that, in Embodiment 8, the powder coating primer composition is prepared according to the formula raw materials shown in Table 5 below:

[0038] Embodiment 9: The remaining technical solutions of Embodiment 9 are the same as those of Embodiment 1, except that, in Embodiment 9, the powder coating primer composition is prepared according to the formula raw materials shown in Table 6 below:

[0039] Embodiment 10: The remaining technical solutions of Embodiment 10 are the same as those of Embodiment 1, except that, in Embodiment 10, the powder coating primer composition is prepared according to the formula raw materials shown in Table 7 below:

[0040] Embodiment 11: The remaining technical solutions of this embodiment 11 are the same as those of embodiment 1, except that, in this embodiment 11, the powder coating primer composition is prepared according to the formula raw materials shown in Table 8 below:

[0041] Embodiment 12: The remaining technical solutions of Embodiment 12 are the same as those of Embodiment 1, except that, in Embodiment 12, the powder coating primer composition is prepared according to the formula raw materials shown in Table 9 below:

[0042] Embodiment 13: The remaining technical solutions of this embodiment 13 are the same as those of embodiment 1, except that, in this embodiment 13, the powder coating primer composition is prepared according to the formula raw materials shown in Table 10 below:

[0043] Example 14: The rest of the technical solutions of Example 14 are the same as those of Example 1, except that, in Example 14, the organic dye brand in the powder coating base composition in Example 1 is replaced by Heliogen® Green from BASF.

[0044] Example 15: The rest of the technical solutions of Example 15 are the same as those of Example 1, except that, in Example 15, the aluminum powder of the powder coating composition in Example 1 is replaced by pearlescent pigment (brand: NB free-bonding pearlescent powder PMW04101NB from Shanghai Jincheng).

[0045] Comparative Example 1: The remaining technical solutions of this comparative example 1 are the same as those of Example 1, except that: in this comparative example 1, the organic dye in the powder coating base composition in Example 1 is replaced by an organic pigment with the brand HELIOGEN BLUE K 6907; the powder coating composition of this comparative example 1 comprises 97 wt% of the powder coating base composition and 3 wt% of the organic pigment.

[0046] Comparative Example 2: The remaining technical solutions of this comparative example 2 are the same as those of Example 1, except that: in this comparative example 2, the powder coating base powder composition is directly used as the powder coating composition of this comparative example 2; this example does not include effect pigments.

[0047] The present application obtains the corresponding powder coating primer compositions according to the implementation schemes proposed in the above Examples 1-15 and Comparative Examples 1-2.

[0048] The powder coating compositions prepared in Examples 1-15 and Comparative Examples 1-2 were respectively used, and the same aluminum plate was selected as the substrate. Each powder coating composition was cured by baking heating, wherein the heating temperature was 200° C. and the heating time was 15 minutes, respectively, to obtain a cured coating, and then a clear coating was further provided on each cured coating (see the photo of the coating obtained in Example 1). Figure 1 The product number of the clear coating is TIGER Drylac produced by Tiger Surface Technology New Materials (Suzhou) Co., Ltd. ® 049 / 00041, clear coat is applied by electrostatic spraying with TIGER Drylac ®049 / 00041 is set on the cured coating, and then cured by baking heating at 200°C for 15 minutes. The performance test comparison results are shown in Table 11:

[0049] After comparative testing, it was found that the powder coating compositions provided in Examples 1-2, 6-7, 10-11, and 13 have outstanding brilliant metallic effects.

[0050] It should be noted that the coating performance test involved in this embodiment is carried out according to the test standard described in Table 12 below.

[0051]

[0052] It should be noted that those skilled in the art can also apply the powder coating composition proposed in this application to the coating protection of other material substrates to obtain similar coating effects, which will not be described in detail in this application.

[0053] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0054] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A powder coating composition having a brilliant metallic effect, characterized in that: The invention comprises a powder coating base powder composition and an effect pigment, wherein at least one effect pigment is attached to the powder coating base powder composition, wherein the powder coating base powder composition comprises an organic dye.

2. The powder coating composition having a brilliant metallic effect according to claim 1, characterized in that: The organic dyes include anthraquinone organic dyes, and preferably consist of anthraquinone organic dyes.

3. The powder coating composition having a brilliant metallic effect according to claim 1, characterized in that: The weight proportion of the organic dye to the powder coating primer composition is 0.1-3 wt %.

4. The powder coating composition having a brilliant metallic effect according to claim 1, characterized in that: The powder coating base powder composition is transparent or at least translucent after being cured.

5. The powder coating composition with brilliant metallic effect according to claim 1 or 4, characterized in that: The raw materials of the powder coating primer composition include polyester resin and a curing agent for curing the polyester resin; the weight ratio of the polyester resin to the powder coating primer composition is preferably not less than 55wt%, more preferably 65-95wt%, and further more preferably 70-92wt%; the weight ratio of the curing agent to the powder coating primer composition is preferably not more than 20wt%, and more preferably 2-15wt%.

6. The powder coating composition having a brilliant metallic effect according to claim 5, characterized in that: The viscosity of the polyester resin at 200° C. is in the range of 1500-4500 mPa.s, more preferably 2000-4000 mPa.s; and / or the acid value thereof is not higher than 45 mgKOH / g, more preferably 25-40 mgKOH / g.

7. A bright color metallic effect coating, characterized in that: The powder coating composition with brilliant metallic effect as claimed in any one of claims 1 to 6 is sprayed on a substrate and cured to obtain the powder coating composition.

8. A bright color metallic effect coating, characterized in that: The invention comprises a cured coating and a finishing coating located on the surface of the cured coating, wherein the cured coating is obtained by spraying and curing the powder coating composition with brilliant metallic effect as claimed in any one of claims 1 to 6 on a substrate.

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